Systematic theology seems in eclipse at the moment.  It is suspected not only of being detached and impractical, but also of using biblical texts in hopelessly non-historical and non-contextual ways.  It’s time, I think, to re-assert the value systematic theology for the preacher.  Here’s a summary of what Donald McLeod has to say on the subject:-

“Theology without proclamation is empty, proclamation without theology is blind.” (Gerhard Ebeling)  “I don’t care anything for a theology that doesn’t help a man to preach.” (James Denney)

Paul saw his own function as being to preach the word of the cross: Christ died, and Christ rose.  But he also had to proclaim the meaning of these facts.  As simple facts, they achieved nothing.  ‘Interpreted as Christ’s vicarious suffering for sin and as the attestation of his divine sonship and lordship, they were the saving power of God.’

Paul, in 2 Cor 5:20f, saw his ambassadorial role as the expositor of a deeply theological message.  ‘It is not enough that the preacher does not contradict that message.  It is, unfortunately, quite possible to be completely nonheretical and yet at the same time totally unfaithful to the preacher’s mandate.  The great theological, christological, and soteriological themes must sound forth clearly.’

Systematic theology draws on both biblical theology and historical theology.  But it is more comprehensive than each.  ‘It seeks for the over-all biblical and historical view, collating all the relevant biblical passages and the contributions made by academic and polemical discussion.  It is final and normative in a way that its sister disciplines are not.  It seeks the final view of Scripture, rather than the transitional one of the Old Testament or even the Book of Acts.  Similarly it not only describes the views of fathers and heretics (in the manner of historical theology), but also evaluates them in the light of the rule of faith.’

Systematics and Exegesis

In general, each text must be seen in the light of the whole system of revealed truth:

(a) The system of truth elucidates each text: this is the analogy of faith.  “The infallible rule of interpretation of Scripture is the Scripture itself; and therefore, when there is a question about the true and full sense of nay Scripture, it must be searched and known by other passages that speak more clearly.”  (Westminster Confession, 1.9)

(b) The system of doctrine exercises control over the exposition of a particular passage.  Because truth is a unity, dogmatics lays down parameters that exegesis must not trespass.  For example, the exposition of Psa 6:5 must not contradict the doctrine of the immortality of the soul, the exposition of John 3:5 must exclude the idea of baptismal regeneration, and that of 2 Cor 5:21 must keep intact the doctrine of the sinlessness of Christ.

(c) No doctrine should be built on a single passage of Scripture.  To do so ‘”is like balancing a stool on one leg.” (A.A. Hodge).  This principle has often been forgotten, especially in the area of eschatology: rapture (1 Thess 4:17), first and second resurrections (Rev 20:4), and millenium (Rev 20:5).

Dangers: we may tend to suppress the doctrine of a particular text in the interests of our own system.  Calvinists may play down the scope of God’s love as declared in Jn 3:16 and 1 Tim 2:4, or minimise the importance of working out our own salvation, Phil 2:12, or mute NT warnings against the dangers of apostasy.

A related danger is that of approaching the exposition of a text that appears in conflict with our doctrinal system by merely providing an apologetical exercise showing how the two may be reconciled: a sermon on Jn 3:16 may end up qualifying and contracting the love of God ‘rather than to show it in the glory of its self-renunciation, magnanimity, and extravagance.’  Again, ‘the preacher faces a text that declares that those who are born of God do not sin (1 Jn 3:9) and spends his strength showing that they do.  The text’s insistence of the anomalousness and monstrousness of sin in the life of a Christian is forgotten.’

It is also a mistake to try to bring out in any one sermon all that systematic theology has to say on the particular subject.  “It is a common delusion of inexperienced speakers or writers to think that they had best take a very broad subject so as to be sure of finding enough to say.  But to choose some one aspect of a great subject is usually far better, as there is thus much better opportunity for the speaker to work out something fresh and much better prospect of making the hearers take a lively interest in the subject as a whole.” (John A. Broadus)  Example: Heb 2:4, where the exposition of ‘so great salvation’ should be limited to those aspects suggested by the context.

The Shaping of a Sermon

Generally, the structure of the sermon should not be determined by dogmatics but by the text itself, along with its context and life-situation.  We should be faithful to the pastoral situation that underlies the text.  ‘To preach Phil 2:5-11 is not only to preach Christology but also to plead for an end to all obsession with our own rights; to preach 2 Cor 8:9 means not only to proclaim the marvel of the incarnation, but also to lay down the biblical theology of Christian giving; and to preach Gal 2:19ff is not only to declare the doctrine of definitive sanctification but also to relate it in the closest possible way to the charge that the doctrine of justification by grace gives an encouragement to sin.  Not only the doctrinal points but the contours and application of the sermon arise from the text itself.’

Neverthess, some texts do lend themselves to analysis using the categories of systematic theology.  Example: Phil 2:5ff (the preexistent, humiliated, and exalted Christ); Jn 3:1ff (the author, nature, results, and necessity of regeneration); Rom 3:24f (the meaning, source, grounds and means of justification).  However, confined with these parameters, such sermons might be too didactic, and would need to be related to the needs, interests, questions, doubts, and even indifference of the congregation.

Covering the System

Should the preacher attempt to cover the main divisions of systematic theology over a period of time?  Answer: (a) our main concern must be to cover the Scriptures, not any human system of doctrine; (b) we are to declare the whole counsel of God and our pattern of biblical exposition must ensure that we do proclaim all the doctrines contained in Scripture; (c) we are to maintain a biblical proportion and balance: avoiding over-emphasis on our personal or denominational preferences.  Let the doctrine of the sovereignty of God undergird the whole of our teaching, but let the doctrine itself be treated only from time to time.  On the other hand, let semrons be frequently steeped in doctrine of Christ since this is the foundation for everything else.

Doctrines of prime importance are those which are (a) necessary for salvation; (b) plainly taught in Scripture; (c) recognised by all faithful Christians, regardless of denominational distinctives; (d) regarded by Scripture itself as fundamental (e.g. the unity of God, Deut 6:4; the atoning death and resurrection of Jesus Christ, 1 Cor 15:3f; the lordship of Christ, Col 2:6; the humanity of Christ, 1 Jn 4:2f; justification by grace through faith, Gal 1:8ff; the resurrection of the dead, 1 Cor 15:19; the new birth, Jn 3:1-15; love, 1 Cor 13).

Maintenance of proportion and balance will be modified by pastoral factors, and by the need to assert neglected or controverted doctrines or protect against erroneous teaching.  Again, the ability of a congregation to assimilate strong doctrine will be affected by its own spiritual maturity.  A poorly taught congregation needs the basics.  See Heb 5:12.

Should the System be Obvious?

Preachers are teachers.  “If it is bad to preach over people’s heads, not to preach to their heads at all is worse.” (James Stewart)  Therefore, preaching should be unashamedly theological.  This includes evangelistic preaching.  Seminal scriptures such as Gen 3:15; 17:7; Jn 3:16; 1 Cor 1:18; 2 Cor 5:18ff are all richly doctrinal.  Evangelism is a battle for the mind.  Its essence is the affirmation and explanation of truth.  “To call upon men constantly to ‘come to Christ’ and to repeat perpetually the words of Paul to the jailor, ‘Believe in the Lord Jesus Christ’ without at the same time telling them who Jesus is, and what it is to come to him, and believe on him, is the merest mockery.  It is using the name of Christ as if it were some cabalistic charm, and reducing the Gospel message to a mere empty formula.  If, therefore, we would be effective preachers, we must be ready to give an answer to him that asks us, ‘Who is Jesus, that I may believe on him? and what was there in his dying that has any relation to me?'” (William M. Taylor)

Theological preaching is the primary means of pastoral care.  It is possible to kill the flock not only with the poison of heresy but with starvation of truth.  It is truth that sanctifies, Jn 17:17; the loins must be girded with truth, Eph 4:14.  Time and again, when the biblical writers were faced with problems of experience and practice, they appealed to doctrine.  See Jn 14; 2 Cor 8:9; Heb 4:14.  Throughout the history of the church, the great preachers have been theological preachers: Athanasius, Augustine, Luther, Calvin, Owen, Wesley.

Theology should not be taught from the pulpit in the same way that it is taught in the theological seminary.  Things to avoid: (a) the use of jargon in the pulpit.  To ordinary people, words like ontology, hermeneutic, eschatology, and existential are mumbo jumbo.  (b) peppering the sermon with learned quotations.  (c) any attempt an an exhaustive presentation of the subject.

Chalmers emphasised that the aim of preaching is not academic exposition, but practical influence.  “The Christian revelation does not end with the intellect, but begins with it.  The credenda are not the landing-place, but only the stepping stones to the agenda.”  Chalmers also said that the preacher must drive the doctrine home to the individual.

Use of Confessions and Catechisms

We can use these documents (a) as aids to exegesis: most of them contain expositions of key texts such as the Ten Commandments and the Lord’s Prayer; (b) as aids to exposition of key topics, such as repentance, faith, and justification; (c) to highlight and explain key phrases, such as Christ’s descent into hell or the expression “elect infants dying in infancy”; or even, occasionally (d) to indicate defects and limitations in the catechisms and confessions (e.g. the statement in the Westminster Confession that the Word of God is contained in the Scriptures).  Notwithstanding this last point, the preacher who keeps within the parameters of the historic creeds and confessions can be assured that he is not preaching a private opinion ‘or introducing doctrines that threaten the peace and unity of the church.’  Moreover, the confessions provide a reliable indicator of the most important doctrines and thus prompt the preacher to be ‘most in the main things’.

Let us preach doctrinally, and let us do so authoritatively, lucidly, and lovingly.

Based on: McLeod, ‘Preaching and Systematic Theology’ in Logan, ed., The Preacher and Preaching, 246-272.